My Peggy 2 clock idea

I’m a bit of a clock guy, and I’ve got a bunch in my house and in my office.  I’ve got bunches of regular analog clocks.  I’ve got my grandparent’s mantle clock that they were given for their wedding in the early 1930s, which we wind with a key and which chimes on the hour in my living room.  In my office I have one of those “rolling ball” clocks as well as a ping-pong clock from Adafruit.

One thing that some clocks show better than others is the passage of time — and sometimes it’s the passage of time that is most interesting to display instead of the exact digital instant that is now.

Here’s the idea:  The front of the peggy is treated like a “pie”, except it’s square.  It shows the fraction of the last and next 12 hours which are day versus night ( calculated from the wall clock time and the longitude and latitude which are configured by the user )  In essence, the “light” and “dark” parts of the current day rotate clockwise, and at a glance you can see how much of the day

As time passes, this display will “rotate” in a clockwise direction, with the current “time” being at what would be 12 o-clock on a conventional clock.  So, this is a small version of the peggy, with white being “lit” LEDs and black being unlit, and a blue border around the 25×25 pixel field.


would indicate roughly noon, on a day near the summer solstice, and this


would be shortly after sunset, again on a day near the solstice.

Here’s a time around noon on a day in late fall, when the day is about 10 hours long.


Here’s dawn on March 21st, the spring equinox ( when the day and night are each 12 hours long )


During the year, as the seasons change, the amount of light and dark will change and along with it the fraction of the clock which is lit up.  Near the winter solstice, only about 1/4 of the leds will ever be on, while in the summer 3/4 of them may be lit.

Other ideas that might be possible ( depending on how much memory code to do the above took to implement )

– The actual time could probably be drawn, either near the top or bottom of the display, using digits roughly 5 x 5 in size.

– the brightness of the leds could vary, so that near the time the sun was most directly overhead the leds were full brightness, and the dimmed as the time got closer to sunset, then slowly brightened again the next day

– perhaps other astronomical stuff — phase of the moon, or the tides — could also be included, although anything terribly complicated probably won’t fit in the memory available


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